


BEHOLD, the Merman!

by alsoann



Category: Supernatural
Genre: F/F, F/M, M/M
Language: English
Status: Completed
Published: 2012-12-13
Updated: 2012-12-13
Packaged: 2017-11-21 01:37:30
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 9,187
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/591976
Author URL: https://archiveofourown.org/users/alsoann/pseuds/alsoann
Summary: <blockquote class="userstuff">
              <p>Castiel is everything Dean never knew he was looking for – smart, funny, hot as hell, and definitely, definitely not human.</p>
            </blockquote>





	BEHOLD, the Merman!

**Author's Note:**

  * For [bellacatbee](https://archiveofourown.org/users/bellacatbee/gifts).



> Title comes from the fabulous movie Splash. If you haven't seen it, you should. But it was a terrific prompt and I hope my giftee enjoys what I came up with! _Interesting, unrelated sea life fact of the day: There are some species of pipefish where the pregnant male can digest the embryos and conserve his resources if he finds his partner less than desirable._
> 
>  **Contains** : References to mpreg in various species, large amounts of nudity, exposure to the elements, sex – mostly non explicit, language, “science” style science - in the same vein as the movie Splash, potential underlying alcohol dependency issues

“What is that, the Eiffel Tower?”

Dean shakes his head, splitting apart another peanut shell. “Statue of Liberty.”

“Huh.” Jo watches him for another minute before shifting. “Ohh. She doesn't have arms yet.”

Dean yawns, debating if he should get drunk or just go home and go to bed. He'd maybe ask her to hang out after her shift is over, but Dean knows she has other priorities now. Priorities he's really trying hard not to begrudge her for. After all, he thinks if he were the kind of person who could find someone and fall for them, he'd do it in a heartbeat. Placing a few more scraps of shells on the bar top, he evens out the picture. “Nah. Not sure what to use for them. “

“Here's an idea.” They both jerk at the sound of Ellen coming up behind them. “How about one of you make yourself useful and go wipe down those tables?”

Jo flashes Dean a grin and scurries off to check on Bobby and Rufus in the corner. 

“What, you don't like my masterpiece?” At Ellen's raised eyebrow, Dean hurries to brush said masterpiece up. He's not really paying attention when the door jingles open, but Rufus' unexpectedly loud laugh causes him to look up.

“Oh my God,” says Jo.

There, standing in the middle of the bar, Rufus and Bobby drunkenly laughing on one side, Jo looking shell shocked on the other, is a very, very naked man.

“You seen him around before?” asks Ellen quietly in his ear. Dean shakes his head. He's lived on the island his whole life and could recognize just about every person on it. He's gotta be a tourist. A naked, slightly damp tourist. With what looks like a piece of seaweed hanging off his shoulder. The man in question looks around the room curiously before his eyes settle on Dean. Smiling slightly, he nods.

“Hello.”

“Uh...” says Dean. Leaning toward Ellen, he lowers his voice. “You wanna call Jody?”

She snorts. “Think we can't deal with one guy?” Dean shrugs, knowing Ellen's more than capable. “Good. Jo, honey. You're in charge. Don't let Bobby get too drunk.” Walking up to the guy, she asks, “You got a name?”

He looks at Dean when answering. “Castiel.”

“All right Castiel. There a reason you show up in my bar naked as the day you were born?”

He frowns slightly, looking down. “I...don't have clothing with me.”

“Let's get him in the back,” says Dean. Ellen nods, guiding Castiel to their small break room. Dean roots around in some cupboards. “Ha!” He manages to pull out an old pair of slacks from back when they were still pretending to be a respectable establishment. “Put these on.”

When Castiel reaches for the pants, Dean plucks at the seaweed on his shoulder. “What'd you do, swim here?”

“Yes.” 

“From where? Canada?” Ellen asks, eyebrows raised high.

Castiel runs his hands over the plastic bench he's sitting on. “From my home.”

The guy looks harmless enough, but it makes sense when Ellen asks, “Are you in trouble with the law or something.”

A shake of his head. “No. I wanted to take -” he pauses, thinking. “A vacation.”

“A vacation.” Dean repeats.

“Yes. A vacation.”

And Dean's not one to look a sort of confused, strange, six feet of lean muscle gift horse in the mouth, so he just goes with it. It's not his fault that the guy is hot. “I got this, if you wanna...” he waves toward the front at Ellen. 

“See if you can find someone to call for him,” she tells him, heading back to the front.

Dean very nearly does that, but somewhere along the way they get distracted by a wayward fifth of whiskey.

Jo finds them after closing, stretched out on the carpet trading drunken kisses.

“Seriously?”

“Wasn't working today anyway,” he mumbles into Castiel's jaw.

“Dean, go home.”

He stands up too fast, swaying. “Fine. Taking my new friend with me.”

Jo has that look of hers that's one part disapproving two parts amused. “I'm calling you first thing in the morning, and if you're dead I'm gonna be so pissed.”

Dean laughs, leaning into Castiel. “Promise not to kill me?”

Castiel leans back, speaking into Dean's shoulder. “Why would I kill you?”

“See?” He grins at Jo. “Safe as houses.”

Dean leaves his car, tossing the keys to Jo – one of the two people allowed to drive her, and stumbles home, Castiel in tow.

~~~

A loud buzzing cuts through his sleep. After a few tries, Dean grabs the phone.

“Are you dead?”

Dean groans. “No. Go away.” 

“You mean, 'thank you for driving my beloved car home, Jo. I'm sorry my life is a train wreck.' ”

He mumbles out a thanks, throwing his phone back down, and tries to fall back asleep, but it's too late. Yawning, he disentangles himself from the body next to him. Dean rubs his eyes awake. As he looks over the man still out beside him, memories start to seep back in. He definitely went home with the naked guy. That's gotta be a new low.

As if on cue, the guy – Casti-something – Castiel, wakes up. Blinking slowly, confusion fills his face as he takes in the room.

Dean grabs his jeans from the floor, yanking them on.

“So. Morning.”

Castiel doesn't respond, flicking instead at the dried mess on his stomach. Dean has a sudden flash to the night before. The guy might be weird as fuck, but he was pretty damn flexible. He clears his throat, feeling his face heat up. “you can take a shower if you want. I'll leave you out some new clothes.” He doesn't know why he's offering, but Castiel looks over at him, eyes wide and earnest. 

“Thank you.”

Dean feels his face heat up even more. “Don't mention it.” He points out the the bathroom to Castiel and finds some clothes he doesn't mind parting with. Pulling on a shirt himself, Dean heads to the kitchen.

He's at the kitchen table with his coffee when Castiel comes out later.

“You want some coffee or eggs or something?”

Castiel shrugs a little, which Dean takes as a yes. Rooting around the fridge, he asks, “so what was your plan? Walk from place to place til you found some clothes?”

“I was looking for you.”

Dean's hand tightens on the carton of eggs. He really should have seen this coming. Of course he's some sort of psycho stalker. Stiffening, Dean straightens up slowly and turns around.

“Look pal-”

“We met each other. When we were young.”

“We knew each other. So you just decided to track me down for old time's sake. While you were naked.”

Castiel frowns. “I told you. I didn't have any clothes. I didn't expect...sex. I just wanted to meet you again.”

“Okay. I don't know you from Adam, so,” he waves his hand around, waiting for Castiel to get the picture and leave.

Instead he narrows his eyes, leaning forward. “You fell off a boat. I pulled you to shore.”

Dean freezes, because there was only one time he ever fell off a boat. He was ten, and he can't even remember what led up to it anymore; he just remembers the splash and it getting harder and harder to breathe. Then he remembers a shy smile. His dad found him an hour later laid out on the rocky beach. The only time he'd ever seen the man crying, but all Dean could do was shout and pull at him, begging for his dad to go find the other boy lost in the water. 

Over time his memories warped until Dean even drunkenly confessed to Sam that he half believed it was a mermaid that saved him. He was never able to live that one down.

“Did Ruby pull you up to this?” he asks, each word slow and measured.

Castiel frowns again, a crease forming between his eyes. “I thought you would have remembered. My body has grown.” He adds thoughtfully.

“Okay. I think breakfast might have to be cancelled.” Dean stalks to the doorway. “It was nice to meet you and all...”

Castiel rises across the table. “You might remember this better.” He holds out his right arm, and before Dean can react, the skin starts to change. It grows shinier, darker, webbing out between his fingers.

“What the hell...” Dean stares, feeling the moment spiral even further out of his control.

“Here.” Castiel brushes past him and instead of calling the cops like he should, Dean finds himself following Castiel to the living room. He stretches out on the couch, kicking his jeans off. Castiel closes his eyes for a long second and then his body changes once again.

“Holy shit,” says Dean, watching the two legs merge. “Holy fucking shit.” Because there is definitely, one hundred percent, a merman sitting on his couch.

He can't stop himself from moving closer. He doesn't even realizing he's reaching out a hand until Castiel nods at him, giving him permission. The fin is thick, and pretty gross. It's shiny and slick with some sort of mucus-like substance. Dean drops his hand and steps back.

Closing his eyes again, Castiel starts to shift back. When he looks human, he sits, pulling his jeans back on.

“So you can turn into a fish,” says Dean, trying to keep the hysteria back.

“ _I'm not a fish_ ,” sniffs Castiel.

“Just half of one.” He sits down on the coffee table because there's a weird wet spot on the couch. 

“I'm a mammal. Like you.”

A small, panicked laugh rises up. “Cas, I hate to break it to you, but I don't think we've got a lot in common.” Castiel shrugs his shoulders in response, while Dean tries to get a grip back on reality. “So what is this? Some kind of mermaid shore leave?”

“It's harder for me to change than it is for others. I rarely do it. Another child fell in the water and I remembered you.” Castiel looks away. “I was curious.”

He holds himself back from pointing out that there's not much in his life to be curious about. Dean can't help but reach out again and touch Castiel's newly human arm. It feels just like his own.

“There's no freaking way this is real.”

Castiel looks back. “Do you still want to cancel breakfast?”

 

Figuring if he's gonna go along with this whole merman thing, he might as well go all out, Dean spends the day alternating between quizzing Castiel about everything under the sun and showing him everything awesome about being human that he can think of. He makes eggs and bacon for breakfast and learns that Castiel picked up English from a combination of excellent hearing and a lot of talking to himself. He drives them out to the theater, making Castiel pick between the only options of cartoon robots in space or a documentary on education; Castiel picks wisely. On the way back, he learns Castiel gets haughty when he's offended.

“Dude, 'junkless' is accurate. I saw your fin thing, and your dick definitely disappeared.”

“Not everyone wants to keep their 'junk' open and vulnerable.”

Dean sputters at the word _vulnerable_ but he doesn't have a good comeback.

The guy's never seen a book before, so he shows off his small collection. Castiel takes about an hour to get through the back cover of one book, but Dean's pretty amazed anyway, considering the lack of reading material of any kind he's probably been exposed to. During his shift at the bar, he slips Castiel drinks, but doesn't really think that through because by the time he gets off, Castiel is too drunk and barely makes it to the bedroom, tripping onto the mattress.

“Your bed is soft. I like it.”

“Way better than sleeping in the water, huh?”

He has to laugh at the way Cas scrunches up his face. “No. Just soft.”

He's waited all day for the moment when one or both of them will run out of things to say, or awkwardly start the goodbye process, but Castiel doesn't seem to want to go, and Dean still has a ton of things he wants to share with him before he does.

“I don't think I like this part,” groans Castiel, hands pressed over his eyes.

“Here, hang one leg off the bed, it'll help with the spins.” He helps to reposition Castiel. “Better?” The groan sounds a lot like a no, but Castiel manages to find a way to pass out anyway.

Before he can stop himself, Dean reaches for his phone, thinking of other things he wants Cas to get a chance to experience.

 _-Plus1 for Xmas-_ he texts Sam.

A second later, the response comes. _-Jo?-_

He holds himself back from a whiny text about how she has a girlfriend now and a shiny new family, because that's unfair and he's a big person, and also Sam would laugh at him. He also decides a text isn't the best place to say he's bringing the merman he met yesterday to dinner. But there's gonna be a million questions if it's just some random date, because it's not just some dinner, it's Christmas.

 _-Ran into guy who saved me when I was 10!-_

It's a good five minutes before the reply. _-Call me tomorrow!-_

Castiel jerks awake when Dean sets the phone down and settles into bed.

“Tomorrow... show you my world...lots of food.” he trails off, flopping back onto a pillow.

Dean yawns. “Fat chance.” He'd have to be an idiot to want to spend a day swimming in that water.

A hand flails, patting his face. “You'll like it.”

“Uh huh. Go to bed, Cas.”

Ten hours later he finds himself standing in the middle of the dive shop, wetsuits and snorkel gear piled around him. While his new gear is getting rung up, he watches Cas staring down at the display case.

“This watch is on sale. Only 99.99!” he says, too brightly for someone drunk off his ass the night before.

Dean looks over at the case. “A: That's a ladies watch. And B: it's a hundred dollars.”

Squinting to read the description, Castiel finally says, “It's stainless steel.”

The assistant, Garth, pulls it out of the case, holding it up. “The band smells like vanilla,” he says proudly.

Castiel sniffs the watch. “Does it?”

“Don't sniff the -” but Garth's waving the watch under his nose. “Yeah, I guess.”

Castiel stares at the watch like it's the greatest thing he's ever seen. Sighing, Dean nods at Garth. “Ring it up.”

Garth smiles conspiratorially at him. “Expensive date!” 

“Just swipe the damn card.”

For the entire ride home, any time Dean glances over Castiel is either beaming back at him or beaming at his shiny new watch. He thinks maybe it isn't the worst purchase he's ever made.

~~~

“I look like a freaking penguin.”

Castiel turns to look at him from his spot on the dock. “I don't know what that looks like.”

“Good point.” he sits down on the edge, trying to attach the giant flippers to his feet. Next to him, Castiel strips off the last of his clothing. Dean still has a hard time believing Cas is about to turn back into some sort of fish thing. When he jumps in, icy saltwater splashes back up on Dean.

“You are gonna owe me so many--” he grumbles, throat catching mid-sentence.

There's no mistaking Castiel for human anymore. His entire body is covered in that thicker, grayish, slimy skin. Even his hair manages to look slimy. Dean takes a few breaths, heart speeding up.

“It helps if you get in the water,” points out Cas, and suddenly Dean remembers it's the same guy he just spent the last day with.

Adjusting his mask, he jumps in.

The water is freezing and Dean isn't really sure why he had to wear this ridiculous wet suit if it wasn't going to do a damn thing. He could be at the bar right now, or sleeping, or okay, he doesn't have too many good options, but with Castiel here, at least Dean could be warm in bed, teaching him about all the perks of humanity.

But he's out here instead, and Castiel's beckoning him forward, so Dean swims out to join him. Castiel is – at home. He moves more naturally, with a kind of purpose he doesn't have on land. It would actually be kind of awesome to see if it weren't so surreal.

They stop to look at a few things Dean hasn't paid attention to since he was a kid wading out in the water – older sand collars and anemones and the tiny urchins that hug his finger when he touches them. Castiel seems to know when Dean's body adjusts to the cold, because he moves out to deeper water and Dean realizes this is really going to happen.

“Ready?” His voice comes out higher, bubbly under water.

Dean nods and they're off. As they paddle out, Dean takes a minute to adjust to the idea that technically, his one night stand is taking him home to meet the family, and that's all kinds of messed up, putting aside the fact that the family lives underwater. Castiel looks so damn happy though, so Dean just focuses on following the flash of his watch as it moves through the water.

They stop a few times for Castiel to show off his world. A weird school of fish that actually hums, bright orange jellyfish that Dean knows enough about to stay the hell away from. Castiel takes him to a small group of fish – long and thin like straws.

“The males, they -” he stops and thinks. “Have children.” Dean frowns, not getting it. Castiel waves his hand around, webbed fingers gliding through the water. “Instead of the females.”

Oh. He lifts his head, spitting out the snorkel. “You're telling me the guys get pregnant?” Castiel nods. “Dude – the water is really fucking weird.”

“It's natural.”

There's something about the way he looks at Dean that makes him pause. “You trying to tell me something?” Castiel just shrugs, turning and diving back under the water. “Hey! That's something a guy needs to know about!” But Cas doesn't stop and no way in hell is Dean gonna be stuck out here by himself so he chases after the disappearing tail.

By the time they come to a stop, Dean's hands and feet are numb. Cas holds an arm out for him. “Do you need to rest?”

But Dean can tread water just fine, thank you, even if he might feel like he's dying. He glares at Castiel. “I'm good.” A ripple runs through Castiel's body that looks something like laughter.

They wait, and after a minute two dark shapes appear, coming closer and closer.

It's a man and a woman, looking at him with unreadable faces.

“My brother...Uriel.” Castiel points. “Call her Rachel.”

“Right.” He hasn't had to small talk many dates' families before, hasn't had too many second dates in general, and he isn't sure where to even start with merfamilies. 'So what do you do?' doesn't seem like a good opener.

Castiel turns to his family and a sudden shrieking sound fills the air.

“What the hell??” Dean splashes backwards.

The two others join Castiel's shrieking. “Uriel thinks you're funny.

“He should see me when I'm trying,” Dean says weakly.

Rachel finally speaks. “It's...nice to see you.” She smiles. “Is that right?”

“Rachel has been practicing,” offers Castiel.

“Oh. It uh, shows. A+.”

She looks back to Castiel and they screech at each other before she smiles at Dean and dives back underwater.

Uriel and Cas keep speaking to each other in that noise that makes Dean wish he could slam his hands over his ears. Occasionally, Castiel turns to ask Dean some really strange question for Uriel, his opinion on different boats and what Dean personally is going to do about pollution getting dumped in the water ( _"Uh, compost more?"_ ) before Uriel too drops away.

“Can you keep going? Uriel says we might be interested in something North of here.”

Dean's exhausted but he reasons that there probably aren't too many times in life where you get to swim with a freaking merman, so he nods, slipping the snorkel past his lips again.

They make it another five minutes before Cas throws an arm out.

“Wait here.” He dives down, far enough that Dean can't see, and no way is Dean sitting around by himself in the middle of the water, so he takes a deep breath and kicks, swimming down as far as he can go.

“Dean!”

He turns around just in time for his flipper to kick at something long and rubbery. Dean might not be an expert on sea life, but he knows enough to know it's a really fucking bad idea to kick a giant pacific octopus. 

He tries to make a break for it back to the surface, but a tentacle reaches out, wrapping around his ankle, and he can't see Cas, or breathe, and he suddenly remembers stories of divers who ran into an octopus and came up dead a minute later. He yanks his leg hard, trying to keep the rest of his body away from the octopus, eyeing it turn that angry darker shade.

But then Castiel bolts in front of him, giant skewers appearing out of his forearms and it's a blur of tentacles and fins and Dean's chest burning like hell, and then Cas is grabbing Dean and dragging him up, up toward the surface.

He gasps, taking in lungfuls of air. Leaning on Castiel, Dean can't even care that he still feels slimy and sort of gross.

After about a minute, he thinks he can talk. “That Uriel's idea of a joke or something?”

“I believe so, yes.”

“Awesome.”

Castiel has to practically drag Dean back to shore, but they make it back. He doesn't climb onto the dock after Dean, though.

“I need to go speak to my brother.”

“Great.” Dean barely has energy left to glare out at the water. “Make sure you tell him how much I'm gonna enjoy fucking his baby brother tonight. In detail.”

A small ripple of laughter and then Castiel disappears again.

It's more than an hour before he comes back. Dean's finally dry and warm, wearing about four layers and lounging on the dock. He's got a six pack with him, and he watches the water wondering how no one else notices the six foot long creature swimming out there.

When Cas finally pulls himself up on the dock, he's all human.

“Now that's my kind of view,” Dean says, setting down his bottle.

Cas lets Dean pull him down by the wrist until he falls to his knees, straddling Dean's lap. Deciding its only right to give Castiel a thorough kissing, Dean pulls him in closer, because a dude who fights off a freaking octopus deserves a solid make out session.

“You taste like salt,” he comments, finally pulling back. Castiel hums in response. Part of him – most of him really, can't believe he has the hots for a freaking fish creature guy. Dean traces his forearm where he saw the blade come out. “Got any other retractable parts I should know about?”

Before he can answer, the sound of voices fills the air. Dean turns his head in time to see Jo and Anna walking out onto the dock.

“Oh sorry -didn't know you guys were – is he...naked again?”

Dean laughs, looking back up at Cas, but the he's white as a sheet, staring at Anna and Jo.

“Cas?”

He ignores Dean, jumping up. Anna meets him in a full embrace, halfway down the dock.

There's the moment of confusion when Dean and Jo can't do anything but stare at each other, and then the two separate. Jo moves about as possessively close to Anna as Dean's holding himself back from doing with Cas.

“You two know each other?”

Anna stares at Castiel. “He's my brother.”

So Dean knows two mermaids. He wasn't sure if his life could get much stranger.

To her credit, Jo takes the mermaid news pretty well, especially for someone who had been seeing one for a good six months. Anna explains that as hard as it is for Castiel to become human – though Dean doesn't think it looks that difficult for him but he's no expert– it is for Anna to become aquatic. She's lived most of her life as a human.

They sit out on the dock swapping stories for a long time after that, and for the first time in a long time he feels warm - part of something real. There's a moment when Anna and Castiel are debating appropriate hygiene and if barnacles growing on someone is something to look down on or not. Jo nudges him and Dean looks over to share the same surreal, _is this really happening_ look that she has. 

It's only when his phone buzzes that Dean realizes how late it's gotten. “Forgetting something?”

“Oh shit, Sam. We -” he tries to think of a way to describe the day. “Got busy.”

There's a pause. “Ew.”

“Dean laughs. Well that too. He uh, took me snorkeling.”

“You? Really?”

“I can snorkel!” Dean protests, walking a little way toward the house.

“I believe you man, I just. Snorkeling? Really?”

There's a pause where he can hear Sam muffled, talking to Ruby and then a shout of laughter in the background.

“I'm gonna hang up.”

“Sorry, I'm here. You must really like this guy. How come we haven't heard about him before?”

“He's new. Look, we'll be there in two days. Tell Ruby to behave.”

Sam laughs. “Fight your own battles, man.”

 

~~~

Before they knock, Dean has to go over it one more time. “Dinner first. Tail presentation second, got it?”

Castiel nods solemnly. “I got it.”

Ruby answers the door. Of course. He doesn't understand the smug little look on her face, and he doesn't trust her as far as he can throw her.

“The guest of honor!” she says, pulling Castiel into the house. “Our Dean here's never brought a date before.”

“Be nice!” he orders.

“Always!” she calls back.

For some reason she's decided to play a Disney mix while they wait for dinner. Dean stands up sharply when it gets to a Little Mermaid song, because there's no way he can watch Castiel's head bobbing along without losing it completely.

He finds Sam in the kitchen, pulling bread out of the oven. “He seems nice,” Sam smiles encouragingly.

Dean rolls his eyes. “Don't start looking into wedding planners.”

“I just mean-” Sam flails for a second. “It's good to see you trying, you know?”

He seriously needs a drink for this conversation. Finding a stray beer in the back of the fridge, Dean takes a few long swallows, wondering if Sam'll just change the subject.

“It's just...” No dice. “Ruby and I? We worry about you.”

“Yeah, I'm sure she really stays up late, wondering if I'll ever find happiness.” Dean smiles brightly. “You know your room's still there, if you ever want to give up this whole thing.”

“My marriage?” Sam sighs, watching him. “This is what I'm talking about-”

“Here we go.” Dean says. “It was a freaking joke.”

“Don't you think you're living in the past a little?”

“You just told me about how you liked the new guy!”

Sam looks worried for a second, shaking his head. “Yeah. It's a really good start. I just hope you're looking for people you might have a future with.”

Dean grabs the basket of bread, not sure where this is coming from and not caring to know. “Whatever. Can we eat?”

Dinner is stiff, and someone – Ruby – decided to skip the steak in favor of crab this year. She looks way too pleased with herself when she announces it. He just wants to get through dinner, announce mermaids are real, and go sleep for a year.

“I know this crab,” Castiel says offhandedly, staring at his plate.

“You what?” asks Sam. Ruby giggles into her wine.

“Yeah! Dungeness. Good stuff,” Dean interrupts, too loudly, glaring at Castiel. They had a plan.

“I named him Phillip.” For a brief second, Dean wants to panic that they've just boiled and cracked open Castiel's friend in front of him, but then Castiel starts to eat the thing, happy as can be.

Ruby erupts into laughter, not even trying to hide it. Trying to salvage the situation, Dean offers Sam a shaky smile. “He's just, uh-”

“Totally a merman.” Ruby's voice is full of glee.

Castiel drops his crab leg. Dean freezes, staring at Sam who is staring at Cas.

“I knew it!” Ruby cries, slamming down her napkin.

“Castiel swallows, glancing at Dean for help.

“Ohmygod, really?” Sam starts to gush. “I didn't want to think, but oh my god.” 

“Hold on a freaking minute. What? And why the hell aren't either of you surprised,” he asks, turning to Sam.

His brother bites his lip. “We um. Might have been doing some research for work?”

“You work for NOAA, not the MIB.”

Ruby flicks a piece of ice at him. “The MIB worked with aliens, dumbass.”

“I'm pretty sure NOAA doesn't work with mermaids!”

“That you know of,” says Sam simply.

Dean takes breath, trying to push the hurt aside about the fact that his brother kept such a huge area of his life from him. “Not cool, Sam.”

“Can I go back to eating Phillip now?” Castiel finally asks, breaking the silence.

Dean stares for a beat before a burst of absurd laughter finds its way out. “Knock yourself out."

 

~~~

The room is dark when he wakes up, bed empty next to him.

Dean follows the faint sounds down the stairs to find Ruby and Castiel huddled together on the couch, watching something on her laptop. He comes around behind them, trying to make out what they're watching.

“You've got to be shitting me.”

“What? It's funny.” Ruby turns the sound up on Ursula's menacing monologue.

Castiel twists around to look up at Dean. “It's also extraordinarily inaccurate.”

He leans over Castiel, watching with them for as long as he can take, considering the fact that it's two in the morning. Rising, Dean ruffles Castiel's hair just because he can. “Whatever. You start singing Part of Your World and it's your funeral.”

“Tough words for someone who knows the name of a specific song from a Disney movie,” Ruby points out.

Dean opts to take the high road, ignoring them and heading back upstairs He drifts in and out until Cas joins him. Dean knows he's getting way too used to the idea of someone sharing his bed, but he just pulls Castiel in tighter.

“I preferred the movie you showed me.”

He mumbles a sleepy affirmation and wants to chase down his dreams again. That plan is interrupted when the pounding starts. And then the cries, from down the hall.

Dean rolls away from Castiel, shoving a pillow over his face. “I hate her. I hate her so much.”

“For having sex with your brother.” He says it like it isn't incredibly disturbing to have to hear.

“She's doing it just to piss me off.” 

Cas peels the pillow off his face, looking down at him thoughtfully. “I don't think that's why they're having sex.”

Dean definitely doesn't pout. “Whose side are you on, anyway?”

He doesn't have long to pout, because Castiel's hand is working its way in an interesting direction. “We should show her you don't care, then.”

Dean's definitely awake now. “You're a sick bastard, you know that?”

Cas flashes him a small smile, ducking under the covers, and then Dean starts focusing more on Castiel's mouth and less on anything happening outside of the bedroom.

The next morning, Sam tries to convince Castiel to come into the lab.

“We can keep your secret if that's what you want. There hasn't actually been any real confirmation of what they think is in the water.”

Arms crossed, Dean stands in the corner watching the conversation. “Then why do you want to take him, other than to do freaky experiments?”

Ruby rolls her eyes. “You're acting like we're talking surgery and vivisections.”

“Nobody's vivisecting anybody,” he snaps.

Sam sits down next to Castiel, voice calm. “You said this is the longest you've been human. This might be helpful, like a visit to the doctor.”

Castiel looks lost, glancing up at Dean for help. He shrugs roughly. “I don't like it, but it's your call.”

“I- my sister struggles to stay anything but human. I'm the opposite.” He pauses. “Except for this week. Can you help with that?”

“We can try.”

They sneak him into the empty lab through the back door. Dean stands in the hallway the whole time. One eye looking out for people coming through, one eye on the little window in the door, watching them work. It's just mostly just taking blood and doing simple tests, but Dean still doesn't like it. He can think of too many reasons why the feds shouldn't find out about Castiel. But he's been outvoted so he grits his teeth and waits.

~~~

 

It's a couple of days later and halfway through a long shift of inventory at the bar that his phone buzzes.

“Hey Dean!”

“What do you want, Ruby?”

“Hate to bother you, but I need a teensy favor?”

Dean shifts the box on his hip. “A personality transplant?”

She laughs, strange and giggly. “We're at work right now, and they think they could use your help with some questions?”

His insides turn to ice, a million worst case scenarios floating through his mind. “What are you talking about-” 

“I know! Well I told them about the three of us spending all Christmas together, but I guess they have some questions? I don't really know? They're talking to Sam about it right now.” She giggles again, voice still unnatural. 

Dean sets the box down in the hall, heading back to the door. “What do you want me to do?”

“Oh I can pick you up, no problem! Can you make the next ferry?”

Numb, Dean agrees. He finds Jo and makes some excuse. They have Sam. They have Sam and they're going to throw him in jail and find Castiel and cut him into pieces. It's only a mile home – a mile out of his way from Sam, but he has to make that detour. He tears down the road, pulling to a stop in his driveway with a screech. Cas is sitting on the couch, reading one of Dean's old books, completely unaware that there are people who want to study him and probably see if they can farm him or something.

“Cas, listen to me. Don't let anyone in the house. Don't leave the house. Don't answer the door. Understand me?”

He stands, looking around. “Yes. Dean, what's happening?”

Running a hand over his face, Dean says “I think they found all the lab work on you. I'll explain later. I've gotta-” he shakes his head and runs back out, locking the door behind him.

He finds Ruby's car on the other side of the water. She looks as scared as he's ever seen her. 

“Tell me exactly what's happening,” he says, getting into the car.

“I'm not really sure. Sam didn't like the way his boss was hovering, and I know he decided to shred all the lab work, just in case the guy found it. Next thing I know, the place is crawling with suits and they're asking me about alibis.” She glances over at him sharply. "It was just the three of us."

Dean nods. “Right. Cas doesn't even exist.”

Ruby's knuckles are white where they grip the steering wheel. She pulls onto the freeway just to slam to a stop behind a line of cars. Dean's stuck with his thoughts, about how he knew this was a terrible fucking idea, and he should have been there with Sam, not dicking around with Cas, and he doesn't even know how much trouble Sam could be in right now.

Ruby's voice comes out smaller, quieter than he's ever heard her before. “They wouldn't even let me talk to him.” For a second, Dean can See what Sam sees, when she doesn't have ten lines of defense up. But then a car cuts her off and she swerves, slamming on her horn, walls back up again. Dean's are back up too, swearing, and their focus is just to get to Sam.

An hour or two of traffic later and they pull into the parking lot.

A couple of burly dudes whisk him away into some room, and nobody tells him anything. Dean tries the door but it's locked. Finally, a woman comes in and asks him to sit.

“Nah, I think I'm good,” he says, standing against the wall.

She shrugs, and spends the next hour grilling him on every detail of this job, his life, his family. There really isn't much to say, but they keep asking the same questions over and over. It's not what he's expecting and he half suspects Ruby must have left something out.

When she's finished, she opens the door and brings him out to a couple of workers. The lab coats take him down a series of hallways into a large room with a tank in the middle. The pieces finally fit together and he realizes they think he's a freaking merman. 

They order him to disrobe and all four stare at him. Relieved, he almost laughs. Dean winks instead. “You're gonna have to buy me dinner first.” But he doesn't really care, as long as the focus is on him and not other ideas; he can take the focus off the truth, Ruby can deal with Sam. If anyone can get Sam out of this mess, it's Ruby. Dean soon finds himself hooked up to a series of tubes and monitors. They guide him up and into the tank.

It's kind of funny at first, but then it just gets boring, and the furious scribbling on their pads dwindles down to on occasional comment. Dean occupies himself by tapping out the melody to his favorite songs and doing pelvic thrusts when he thinks someone's staring a little too hard at his body.

Ten hours after his lunch break at the bar, Dean's stomach can't take it any more. “Think a guy could get a little dinner?” he shouts.

Five minutes later they dump a live fish in the tank. He sighs, not even bothering to throw out an obligatory sushi joke.

He's in the middle of reciting his top one hundred favorite musicians, just to piss them off, when someone new enters the room.

“Thank you for your cooperation,” she says. “We'll just ask you sign some confidentiality agreements and then you're free to go.

“Where's Sam?”

“He's signing his own papers in the hall as we speak.”

“So we're all just going to forget the fact that you made me stand in a tank for five hours?”

She smiles. “I'm glad we understand each other.”

A couple of suits escort the three of them back out to the parking lot. They find Ruby's ridiculous car and Dean breathes a sigh of relief, home free. No vivisections today.

“That wasn't exactly how I wanted to spend my evening.”

As Ruby pulls out onto the main road, Sam turns in his seat. “You wanna check in with Castiel and make sure he's still okay?”

Dean sits up. “You think they tracked him? They seemed pretty sure it was me or nothing.”

Sam frowns, then looks over at Ruby. In the rear view mirror he manages to catch a look of guilt flash across her face. “I didn't think-”

There's the bomb that he should have been waiting for, that he used to be so good at anticipating.

“Sam? What the hell is going on?”

His brother twists back to Dean. “I'm going to ask you something and I need you to promise not to freak out.”

“Sammy...”

“Can you remember the last time you saw Castiel?”

“Yeah, right before I left.”

“Did you touch him?”

Dean frowns. “Did I- what?”

“Before I shredded the paperwork, we noticed something. In his blood.” Sam gets the rest out in a rush of technobabble and words Dean isn't sure really exist, but he gets the gist of it. In a flash, he's pulling out his phone and fumbling with the keypad.

“You're telling me he needs contact with humans to stay a human?”

“Exactly,” says Ruby.

“That would have been really fucking good to know right before I locked him up in my house, completely alone.”

No one answers when he calls Jo, and Anna doesn't pick up her phone either.

“He's probably out in the water right now,” offers Ruby.

Dean wishes that were true, but some part of him knows that isn't what happened. He just needs Jo to check on him. He tries again, still getting her voicemail.

“You were on the phone with me Ruby. Why didn't you say anything?”

There's no guilt this time, just her jaw clenched. “I'm sorry, I was a little preoccupied with the federal government putting my husband in handcuffs.”

“Guys,” says Sam. “Let's just get to the ferry and figure it out from there.”

But Dean is pissed, and he's pissed that Sam isn't pissed, and he's pissed that Ruby is Ruby.

“You know, if you had one goddamn thought that wasn't about yourself I think the world might explode.”

She honks her horn at a passing car. “You're one to talk, Mr. I Don't Want My Brother to Be Happy Because I Hate My Own Life.”

Dean presses the call button again, taking in the blow. “Screw you, Ruby. Just because I didn't want him to marry some -”

“At least I'm not a fucking fish.”

“ _He's a damn mammal_.”

“Have you even thought about the fact the government is breathing down Sam's neck right now? What the hell is your problem?”

She's right. He should have been thinking about Sam, but his priorities are all fucked up and now he's taking Sam along to get even further into this mess. He shoves those worries all down, hating the fact that he can even do that these days. 

“Both of you cut it out!” Sam turns to Ruby. “I'm fine. We're fine, and it's over.” He turns back to Dean. “I'm sure Castiel can tell when he needs to change. He's probably swimming in the water right now, waiting for you to come back.” They both huff a breath out, shutting up. “God.” Sam runs a hand through his hair. “Sometimes I swear I married my brother.”

Dean closes his eyes, dialing Jo again. Then Anna again. Then texting them both. She picks up while they're boarding the ferry. 

“I got your message.”

“Please tell me he isn't in the house.”

“Hold on, I”m going in now.” There's a pause. “I need to call you back, Dean.”

~~

It would be funny looking if it weren't so horrifying. A six foot long merman stretched out across his kitchen floor. But Anna's reapplying wet cloths to him, and Dean can see his skin looks almost green. He runs over, putting a hand on his cheek. It's too dry beneath his fingers; he can almost imagine it flaking off under him.

“Shouldn't he turn back?”

“He's sick,” Anna says. “I couldn't lift him.” 

Dean nods. “Ruby, get the door.” He doesn't even have to ask Sam, his brother is right there, lifting Castiel up by the other end and between the two of them, they manage to get him outside and down to the dock. Dean stares down at the water, not wanting to just dump an unconscious Cas in.

“Hold on,” says Anna, as she kicks off her shoes.

“I thought you couldn't change like that?”

“It'll just hurt. I can do it.” She jumps in half clothed, and they manage to lower Castiel down to her. The two of them disappear and Dean doesn't know what to do.

“They'll be fine,” says Sam, frowning out at the water.

Screw that. Cas should have come up by now, or Anna. Something should have happened. Dean can't just stand around waiting. He takes a breath and jumps in.

The water is so cold that for a few seconds Dean feels like his chest collapses and he can't actually physically breathe. He tries to calm himself down, taking shallow breaths when he's able. Sam's shouting behind him, but Dean needs to do this. He dives under again and again, looking for either Anna or Castiel. He's the one who trapped Castiel in the house.

It gets hard to move his arms, so Dean treads water for a second. Behind him, Sam is waiting out into the water, still yelling at him about hypothermia. 

“I”m fine-” he gets out, teeth clacking. “See? Means I'm fine.”

Sam takes a few more steps out, only stopping when Ruby starts yelling again from the dock. It's getting hard to focus, but he thinks between the two of them they convince Sam not to go out any farther. They don't need any more people getting sick, especially not Sam. It becomes too hard to to talk, so Dean focuses on breathing, surprised he doesn't actually feel cold anymore. He's swallowing a shit load of salt water each time he relaxes and his head dips below the water, and his heavy boots don't seem to be helping matters.

More and more he's convinced that something went horribly wrong with Anna. Each dive down turns up nothing, and each time it's hard to fight back up to the surface. After the voices behind him go quiet for awhile, something hits his head. Dean squints at it, head dipping below the water for a second, before he realizes it's a life jacket. Looking back, Ruby's got another one in her arms, but she's busy shouting at Sam again, so he doesn't bother using up energy to thank her.

Then Sam's voice cuts through the din - _thirty seconds_. It takes a little longer to process than is probably good, but Dean finally gets he means thirty seconds until he's dragging Dean back. Time for one more dive down. 

When he swims back up to the life vest, Dean's reached the point where he's seriously starting to worry that he's not actually cold. He manages to feel something slick brush past his legs, moving up, until arms wrap around him and Dean breaths out in relief.

Castiel's skin feels healthier, slick and warm, and Dean never wants to feel that dry, chalky texture again. Finally exhausted, he closes his eyes.

Dean can't really tell, but he thinks his arms are slipping so he just clings harder. “I'm so fucking sorry,” he manages to get out.

Castiel says something soft, but it's hard to hear, and everything goes fuzzy. Dean feels them slowly moving back to the dock, and he might be out of it, but he swears to god that fucker starts humming that Little Mermaid song. He opens his eyes again to see Anna, getting wrapped up in towels by a frantic Jo, then Sam's face looming in front of him.

~~~

He wakes up again in bed, wrapped up in clothes and piled under every blanket they could find. 

“You're such an idiot, you know that?”

It hurts to turn his head, almost as much as it hurts to breathe, but he meets Sam's gaze.

“Not really my best plan,” he gets out, voice hoarse.

Sam rolls his eyes, and stomps out of the room. He comes back a minute later with a mug of something.

“Drink.”

Dean looks at it. “Water?”

“Maybe you should think about stocking your cabinets with something other than coffee and booze. Just drink it.”

Dean struggles to sit up a bit more. "Anna?" 

"She's okay. Jo's here and taking care of her. Drink." Dean's hands don't want to work, so he has to let Sam help him with the mug while he sips at the warm liquid. He can tell it can't be too hot, but it still feels scorching going down his throat. When Sam's satisfied, he replaces the mug with a small bag of chips. “Eat.”

“I'm fine, Sam.”

His brother fixes him with a glare. “Good. Then eat.”

It's hard to hold the chips, but he preventatively glares back at Sam. “If you try to feed me, so help me...”

Sam goes quiet for a few minutes. He can hear Ruby moving around in the kitchen.“There was a time when I would have jumped right in there with you, even if you refused to leave. I don't know why I didn't, you know?”

“Somewhere along the way you started listening to your genius wife,” says Ruby from the doorway, voice is softer than normal.

Starting to feel more alert already, Dean has to laugh, turning into a cough. “I'm glad you didn't. No sense in both of us getting sick for no reason. 'Sides, I need someone to play nursemaid, since he's out for the count.” He jerks his head toward Cas, laying beside him.

As if on cue, Castiel rolls over and promptly throws up. Dean has never known relief the way he feels it when he realizes someone had set up a bucket on the side of the bed. Ruby rushes over and helps Castiel rinse his mouth out with water. Dean has to do a double take when she even starts to _fuss_ , brushing hair out of Castiel's face and speaking quietly to him.

“How come you're so much nicer to him?” asks Dean, definitely keeping the whine out of his voice.

“I like him more.” But she smiles at Dean when she says it and he can't help but smile back. If he didn't know Ruby well enough to know she'd laugh in his face, he'd thank her for tossing him the life jacket. Or maybe take back _some_ of the things he said about her in the car. Either way, he thinks that even if they'll never be friends, it's okay; they're much more fun the way they are. 

“Well,” she says, moving to the door. “I think we've all learned a valuable lesson. Something about why interspecies romances don't ever work out.”

“Ruby. Not now.” Dean can see the look on Sam's face, despite his words. He's in for some lecture later about taking care of himself and life choices and he doesn't really want to hear it. He's happy, aside from the almost drowning and bout of hypothermia. More than he's been in a long time. At least he feels alive.

“I'm happy,” he tells his brother, right when Cas leans over to puke again. Sam stops to take care of him, then looks back at Dean. 

“Really?”

Dean's grateful Castiel keeps his back turned to them, giving them a small amount of privacy. “Yes, really. My life's pretty damn awesome...minus you know, today.”

His brother smiles at him, seemingly satisfied for now, and then starts fussing again, pulling the covers around. Dean throws his arm out, even if he can't really move his fingers yet. "Hey - I'll say this for her. Ruby's got good taste. You, Cas..." 

Sam frowns at his arm, pushing it back under the blankets. "Is this your 'I'm happy that you're happy' speech?" 

Dean coughs and Sam helps him drink more of the warm water. "Something like it." 

Shaking his head, Sam says, “stop squirming and get some rest.” He pulls one of the blankets over Dean's head, trapping him underneath.

“This is really stupid, Sam. I'm already warming up.”

He tugs the blanket up over Castiel's head too. “The internet said this can help.”

It's dark under the covers, but he can still see Castiel trying not to laugh next to him. Sam pats him through the covers and says he'll be back in a few minutes.

“No funny business,” Sam orders, as he clicks the door shut behind him.

It's a minute before either of them speak. “You need to be more careful” says Cas finally.

“You need to follow your own advice” Dean snorts back. “Seriously, what the hell were you thinking? Just going to sit around my living room until you dried out completely?”

“You asked me to stay, and I – I thought I was more in control of my body than that.”

Dean sighs, wishing he would have just thought things through and told Castiel to hide in the water. “How are you feeling?”

“Sick.” There's a beat of silence and then, “I want to go home.” Dean tries to come up with something witty to say to show that he totally gets it, and sure maybe he had a realization that his life is pretty cool, but that doesn't mean Castiel has to have the same realization; there's no good reason why he would want to be stuck on an island with a guy who doesn't do much other than complain all day, especially when he could freaking die way too easily, and dry out on the kitchen floor if he doesn't get enough cuddles. Castiel starts to speak again. “But...I want to be able to come back also.”

Huh. “Did Anna tell you how you change?” Castiel nods. He finds Castiel's wrist in the tangle of sheets and blankets and taps the watch he never seems to take off. “So what? We make some sort of schedule and I meet you on the dock and hold your hand until you're a real boy?”

Castiel's eyes dart away. “I shouldn't ask so much, I know.”

“No, I-” Dean rubs his face, wincing when his fingers start to tingle back to life. “Is that really what you want?” That same shrug of his shoulders that always seems to mean yes. And Dean thinks – well he thinks it's a ridiculous idea, but he thinks it could work.

“Can we talk about this sometime when we're not huddled in some weird-ass blanket fort?”

“Of course.”

There's a lull, then Dean just has to know. “Cas? Please tell me you singing Part of Your World was all in my head?” 

“It was technically the reprise.”

“Oh. Well that's not weird at all.”

Shifting, Castiel takes Dean's hands between his own.

“I know something else you could warm up,” suggests Dean, half serious.

Castiel repeats the order, voice stern. “No funny business.”

Laughing, he pulls Cas closer. Dean still doesn't really have any idea what makes Castiel tick – in non cutting people open and doing freaky experiments on them terms. But he's kind of excited to find out.


End file.
